Boeing could twist the knife into struggling European rival Airbus next week as it is set to dominate Britain's Farnborough air show with a stream of new orders for its 787 Dreamliner and other jets.

The timing could not be worse for Airbus, whose five-year reign as the world's leading commercial jet builder looks likely to end after slow sales of its delayed A380 superjumbo and indecision over its mid-sized A350.

"Boeing's spent the last few Farnborough and Paris airshows getting away from the whole orders game, but this time the rumor is that they are back," said Richard Aboulafia, an analyst at aerospace consultants, Teal Group.

"You wonder how much of the show will be people just walking over and giving a good, solid kick to Airbus."

The last month has been painful for the European company. Shares of its parent EADS slumped in mid-June after Airbus announced the second major A380 delay, which ended up costing the jobs of Airbus's chief and EADS's French co-chief.

EADS has lost a third of its market value this year, while Boeing's shares are up 15 percent, hitting an all-time high in May. Boeing led Airbus 480 to 117 in firm plane orders for the first half of the year.

While much of the talk at the airshow is pure marketing, and not all agreements turn into actual orders, Boeing could inflict real pain on an already fragile Airbus if it wins orders from key customers for mid-sized and large jets.

"An Emirates order for the 787-10 would be serious," Aboulafia said. "A firm order for the passenger version of the 747-8 from a blue-chip carrier such as Cathay Pacific would be a real blow."

Industry-watchers have long expected a stretched version of Boeing's popular mid-sized Dreamliner, already being referred to as the 787-10, although it has not officially been launched.

A firm order from Emirates, or another major airline, would get the new model off to a strong start and particularly hurt Airbus, which still has not announced a competitor to the lightweight, fuel-efficient 787.

Airbus held up plans for its mid-sized A350 earlier this year after customers complained that it could not compete with Boeing's carbon and titanium 787, and is expected to announce a radical redesign at Farnborough or shortly after.

Dubai-based Emirates is one of Airbus' major customers for the A380, and has said it is in the market to buy up to 100 mid-sized planes, once planemakers' offerings are finalized.

Qatar Airways could pile on the pain for Airbus. The Middle East carrier agreed to buy 60 A350s last year but said in May it was reviewing its options. The airline, which also agreed to buy at least 20 of Boeing's 777s last year, may convert those into firm orders, industry watchers say.

At the very top of the market, Airbus is also in jeopardy.

With embarrassing delays hampering its double-decker A380, which will be the world's largest passenger plane when it enters service later this year, some customers may opt to stick with Boeing's tried and tested 747 line-up.

Boeing has so far sold only one 747-8 Intercontinental -- a passenger version of its largest cargo plane that can seat 450 people -- but some expect more orders.

"That would certainly put Airbus on notice that they don't have that jumbo market all for themselves," said Paul Nisbet at aerospace specialists JSA Research. "They (Airbus) have enough trouble already getting orders. You don't need that when the rest of your wide-body models are in trouble."